1. Field of the Invention
The present invention relates generally to a laminated heating body to be used as heating body for a disposable warmer and so forth, for example. More particularly, the invention relates to a laminated heating body which can arbitrarily set a temperature on a surface of a sheet.
2. Description of the Related Art
A warmer, such as disposable warmer, is a laminate body of a heating body and a cover sheet wrapping the heating body. The cover sheet is typically formed into a bag shape for achieving a function for sealingly enclosing the heating body received therein and a function for transmitting heat generated from the heating body to a user skin. In case of the conventional disposable warmer, the cover sheet is formed from non-woven fabric or the like.
On the other hand, in Japanese Unexamined Patent Publication No. Showa 64(1989)-034363, an invention relating to a heating device featured in a surface member covering a heating body is disclosed.
The heating device disclosed in the above-identified publication has a surface film covering the heating body, in which the surface film has gas permeability. A plurality of adhesive tapes having a function for blocking gas permeability of the surface film, are fitted on the surface of the surface film. By peeling off the adhesive tapes, an exposure area of the surface film having gas permeability can be varied to adjust a supply amount of air contributing for oxidation reaction of the heating body and whereby to control temperature profile.
However, in case of the disposable warmer, in which the heating body is covered by a non-woven fabric as in the prior art, efficiency in transferring a heat generated by the heating body to a skin of a user, can be low.
On the other hand, in case of the heating device disclosed in the above-identified publication, gas permeable area of the surface film is adjusted by peeling off the adhesive tapes to adjust the supply amount of air contributing for oxidation reaction of the heating body, as set forth above. However, it is actually difficult to control heating amount of the heating body by controlling oxidation reaction of the heating body. Therefore, heating amount can be lacking or excessive to cause difficulty in setting an optimal temperature.